We are planning our trip to Europe for mid May and have already booked our flights with our 19 and 21 year old daughters. We are going to fly into Paris and two weeks later fly out of Rome. I am planning 4 days in Paris and 3 days in Rome but need to figure out what we are going to do in between, really would like to do Cinque Terra and potentially Florence. Please note my husband and I have been to Paris but 20+ years ago and have spent a week in Rome/Venice. I have also traveled to Bavaria several times. We would like to travel via rail but are open to flights. Any suggestions would be appreciated!

How many hotel nights do you have total? Do you have 5 nights in Paris and 4 nights in Rome? I'm trying to figure out if you have 5 nights left (14-9=5) before making suggestions.

Same question. How are you counting days?
It looks like you are left with perhaps 5 nights = 4 full days for the portion you are asking.

A simple internet look up will tell you that a train trip from Paris to Rome is about 15 hours. If you do this, you will be left with 3 full days = one place to visit. If you want more than this and a remote possibility of two place, you need to fly Paris to somewhere Italy such as Paris-Milan, Paris-Pisa, Paris-Genova, Paris-Florence, etc

I am considering something pretty similar with my husband and (then) 18 year old niece next summer. We are considering the overnight Thello train from Paris to Venice:
http://www.seat61.com/thello-train-f...s-to-italy.htm

We like the idea of not flying, arriving right in the city center, and not wasting too much daytime hours traveling.

Happy travels!

We are arriving on Saturday morning the 13th of May in Paris and I was planning on leaving Paris either the 16th or 17th. My plan is to book at least on tour from Viator while in Paris. We depart on the 26th from Rome - plan is to arrive in Rome on 23rd and do tours on the 24th and 25th. I presently have no plans from the 17th to the 23rd but would like to do Cinque Terra for two days. Any advice on where to go from Paris would be appreciated!

Does the experience for your children matter very much or are they just coming along? If you were only briefly in Paris 20 years ago it will be almost as new to you as to your children. Advise 3-4 full days plus a half jet lagged first day for Paris. Rome is a more difficult issue as you have been there briefly sometime in the near? past. Rome also probably deserves 3-4 full days for a first time. It is therefore a bit difficult to see exactly how much time you have in the middle. If you leave Paris in the early evening of the 17th you would have almost 4+ days in Paris and if you arrive in Rome in the evening of the 22nd you would have 3 full days in Rome. This shortchanges your daughters experience in Rome a bit but it may be a decent compromise. This gives you somewhere around 5 days in the middle. One simple route is to fly to Florence for four nights and than do some day trips if you want to. The CT is however a very long day trip from Florence and one I would find difficult to justify given the time needed to get there/back.
Siena, Pisa, Lucca are much closer. Could consider 2 nights in Florence than travel to the CT for 2 nights but that would shortchange both the CT and Florence.
One alternative to your plans is something a little different since you prefer rail to flights. Take the TGV to Nice in the evening of your last day in Paris. It takes about 5 1/2 hours. Spend the night in Nice than take the train from Nice via Genova to the CT which takes about 5-6 hours along the coast. Spend 4 nights in the CT than train to Rome. Could also spend a second night in Nice and 3 nights in the CT, which would give a day in Nice. In any case you could play with these dates to suit the needs/desires of the group. My last advice is to keep things as simple as you can make it and that less can be more.

>>>My plan is to book at least on tour from Viator while in Paris<<<

FYI - Viator is a reseller. They are selling tours of other companies.

To have 3 sightseeing days in Paris, you would need to stay until the 17th.

To have 3 sightseeing days in Rome, you would need to arrive on the 22nd.

17th - Depart Paris, fly to Pisa on Easy Jet from Paris Orly airport (you don't have time for trains). Transfer via train to CT. You would need to stay until the 20th to get 2 full days. Most of the 17th would be taken up with travel.

20th - Transfer via train to Florence. Stay in Florence until the 22nd when you would catch the train to Rome. You could take a later train to Rome (store your luggage at the train station if your hotel doesn't store luggage).

https://www.easyjet.com/en/

A few years ago we took the overnight train from Paris Bercy station to Rome. We had our kids, so there were 5 of us in a sleeper car and we had a blast. We woke up in Rome rested and ready to go..... As I remember the sleeper slept 6, so we were advised to buy 6 spots instead of 5 to have the room all to ourselves. It was really fun because we got to meet people from all over Europe and it was an adventure for our kids. I think the train stopped in Florence and a few other spots on the way.

I don't think that there is still an overnight train between Paris and Rome that will not require at least one and possibly two connections. Overnight trains are being phased out, I believe.

Getting to Cinque Terre from Paris is going to take most if not all of a day by train and be difficult. I would fly to Genoa from Paris to go to Cinque Terre and go from there to Rome and skip Florence or fly to Florence and skip Cinque Terre. I don't think that you have enough days to do them both justice.